FAIR VALUE MEASUREMENTS AND FINANCIAL INSTRUMENTS - Acquisition-related Contingent Consideration Obligations, Reconciliation of Contingent Consideration Obligations (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation
Balance, beginning of period	$ 328	$ 316
Acquisition-related contingent consideration	0	24
Payments	(49)	(24)
Foreign currency translation adjustment included in other comprehensive loss	1	0
Balance, end of period	280	316
Current portion included in Accrued and other current liabilities	74	37
Non-current portion	206	279
Accretion for the time value of money
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation
Acquisition-related contingent consideration	9	11
Fair value adjustments due to changes in estimates of other future payments
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation
Acquisition-related contingent consideration	$ (9)	$ 13

Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled within one year or the normal operating cycle, if longer.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled beyond one year or the normal operating cycle, if longer.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Amount of gain (loss) recognized in other comprehensive income (OCI) from liability measured at fair value on recurring basis using unobservable input (level 3).

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Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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